The Florida Pediatric Community Clinical Oncology Program is a consortium of the following five Florida hospitals and one hospital in Puerto Rico: 1) Joe DiMaggio Children's Hospital, 2) The Children's Hospital of S.W. Florida - Lee Memorial Health System, 3) Nemours Children's Clinic-Orlando, 4) Nemours Children's Clinic at Sacred Heart Children's Hospital, 5) San Jorge Children's Hospital, and 6) Tampa Children's Hospital. The CCOP has been continuously funded since 1983 and has the Children's Oncology Group (COG), previously the Pediatric Oncology Group (POG), and the H. Lee Moffit Cancer Center CCOP Research Base (HLMCC) as its research bases. It is among the single largest contributor of patients to treatment studies in COG over this 21 year period. The CCOP consistently has outstanding compliance scores and contributes to the administration and science of COG through its members who chair or co-chair active COG protocols. Altogether, they complement the university teaching hospitals and other hospitals in the State which are also Children's Oncology Group members. The CCOP geographically covers the entire State of Florida and provides oncology care to the entire population of Florida, the fourth largest state in the country. The CCOP hospital in Puerto Rico services the entire island and the neighboring Caribbean islands and is the major contributor of minority patients to active studies. The goal of the Florida Pediatric CCOP is to make available the latest advances in cancer care to patients in Florida and Puerto Rico through participation in clinical trials and to register the majority of their eligible patients on COG protocols, thereby providing quality care in patients'home communities. The Moffitt CCOP Research Base is a recent affiliation to enhance availability of cancer prevention and control studies. The CCOP provides a unique opportunity to study a geographically-defined population to investigate risk factors, patterns of care, and population-based interventions. The Florida Pediatric CCOP also maintains the CCOP Patient Log which affords the opportunity to ensure the majority of eligible patients are registered on appropriate COG protocols. Overl94 patient registrations are anticipated per year on COG treatment protocols and 38 on protocols approved for cancer control credits per year through the 6 Florida Pediatric CCOP participating centers. COG and Moffitt quality-control procedures apply uniformly to the Florida Pediatric CCOP, ensuring compliance with protocols and external review of pathology, radiotherapy, surgery and chemotherapy.